Review of inspection techniques based on the elastic and inelastic scattering of X-rays and their potential in the food and agricultural industry

X-rays that are elastically or inelastically scattered from a sample provide valuable information about the internal characteristics of a sample such as the molecular structure, density and atomic number. Also since the field of view of the source and detector can be defined, by selecting the incident and scatter angle it is possible to examine the properties of a small volume element of the sample, rather than the integrated information more commonly obtained from a transmission image. This paper reviews the current status of inspection techniques that are based on the scattering characteristics of X-ray photons by a material and the applications to which these techniques have been applied. The opportunities of these methods within the agricultural and food industry are then discussed and specific areas for future research and development are suggested.